Low-level electrical and communication interfaces to enable charging and discharging of electric vehicles with respect to the grid is described in U.S. Pat. No. 5,642,270 to Green et al., entitled, “Battery powered electric vehicle and electrical supply system,” incorporated herein by reference. The Green reference describes a bi-directional charging and communication system for grid-connected electric vehicles.
Current power flow management systems have a number of drawbacks. Simple timer systems merely delay charging to a fixed off-peak time. There is a need for the implementation of charge patterns for electric vehicles that provide a satisfactory level of flexibility, control and convenience to electric vehicle owners. Purely schedule-based system cannot address unpredictable operational demands.
Significant opportunities for improvement exist in managing power flow at the customer level. Modern electric vehicles could benefit in a variety of ways from a smart charging program that provides electric vehicle owners with guarantees and benefit analysis that assist vehicle owners while coordinating the charging activities of a number of vehicles in an efficient manner.